$base-color:green;
@mixin container {
  width: 300px;
  height: 400px;
  background-color: pink;
}
h1 {

  color:$base-color
}
div{
  a{
    &:hover{
      color: $base-color;
      font-size: 24px;
    }
  }
  p{
    color: $base-color;
  }
}
body{
  @include container;
}